1. Field of the Invention
The present invention relates to working vehicles.
2. Description of the Related Art
A working vehicle has been proposed that includes a cover that is located below a bonnet covering a drive unit and is removably attached to a traveling machine assembly. An example cover attachment structure in such a working vehicle is described in, for example, JP 2004-122877A (particularly, FIG. 4). In the cover attachment structure of JP 2004-122877A, two attachment holes are provided in a lower end portion of the cover, two (upper and lower) horizontal plates are provided on an inner surface of the cover, engaging/retaining pieces are provided in a lower portion of the traveling machine assembly, corresponding to the respective attachment holes, and an engagement/disengagement mechanism with or from which the horizontal plates are engaged or disengaged is provided on the traveling machine assembly.
In the case of the above structure, the cover is attached to the traveling machine assembly as follows. Initially, the attachment holes of the cover are engaged with the engaging/retaining pieces while the cover is held in an angled position with respect to the transverse direction of the traveling machine assembly. Next, while the attachment holes and the engaging/retaining pieces are maintained engaged together, the cover is swung around the attachment holes as a pivot to an upright position so that an upper end portion of the cover is raised toward the traveling machine assembly and the horizontal plates of the cover are then engaged with the engagement/disengagement mechanism. Thus, the cover may be attached to the traveling machine assembly.
Another working vehicle has been proposed that includes an exhaust device that includes an exhaust path through which exhaust gas from an engine is emitted to the outside, and an outside air introduction portion that is provided at an intermediate point of the exhaust path to introduce and mix outside air into the exhaust gas.
In the above exhaust device, the outside air introduction portion may allow outside air to be mixed into the exhaust gas from the engine, whereby the exhaust gas having reduced exhaust temperature may be emitted to the outside. For example, the outside air introduction portion includes a first flow pipe having a smaller diameter and a second flow pipe having a larger diameter. A downstream end portion of the first flow pipe and an upstream end portion of the second flow pipe form a double-pipe structure in which the first flow pipe is located inside the second flow pipe with a gap being provided between the first and second flow pipes (see, for example, JP 2012-60955A). The double-pipe structure may allow for an ejector action on exhaust gas flowing from the first flow pipe to the second flow pipe, whereby outside air may be introduced through the gap between the first and second flow pipes to be mixed into the exhaust gas, so that the exhaust temperature may be reduced.